Contrarians and consensus: The case of the midwife toad

I recently came across an old copy of Arthur Koestler’s “The Case of the Midwife Toad”. Originally published in 1971, it’s an exploration of a rather tragic footnote in the history of evolutionary science. Back in the early years of the 20th Century (prior to the understanding of DNA, but after Mendelian genetics had become well known), there was still a remnant of the biological community who preferred the Lamarckian idea of the inheritance of acquired characteristics over the Darwinian idea of natural selection of random mutations. One of the vanguard for the Lamarckian idea was Paul Kammerer whose specialty was the breeding of amphibians that apparently few others could match. He claimed that he could get his toads and salamanders to acquire characteristics that were useful in the new environments in which he raised his specimens. This was touted loudly (in the New York Times for instance) as proof of Lamarckian inheritance and Kammerer was hailed as a ‘new Darwin’. It all ended very badly when one toad specimen was found to be faked (by who remains a mystery), and Kammerer killed himself shortly afterwards (though there may have been more involved than scientific disgrace).

The details of the experiments and controversy can be read online (with various slants) here and here, and a more modern non-replication of one of his experiments is described here. However, the reason I bring this up here is much more related to how the scientific community and Koestler dealt with this scientific maverick and the analogies that has for the climate science and its contrarians.

There are (at least) four points where the analogies with climate science are strong: First, there were clear philosophical motives for supporting Lamarckism (as there are for denying human effects on climate change) (see below). These are strongly articulated in Koestler’s book, and it is obvious that the author feels some sympathy with that argument. Second, there is idealization of the romantic notion of the scientist-as-hero, sacrificing their all (literally in Kammerer’s case) for the pursuit of truth in the teeth of establishment opposition (cf Svensmark). Third, there is the outrage at the apparent dirty tricks, rumours and persecution. Finally, there is the longing for a redemption – a time when the paradigm shift will occur and the hero will be proven right.

Enough time has passed and enough additional scientific evidence has been gathered however to show that Kammerer’s ideas are never going to be accepted into the mainstream. Therefore, we can use this episode to highlight how people’s misunderstanding of scientific process can lead them astray.

So let’s start with the non-scientific reasons why Kammerer’s ideas had resonance. Martin Gardner in Fads and Fallacies in the Name of Science (1952) puts it well (p143):

Just as Lamarckianism combines easily with an idealism in which the entire creation is fulfilling God’s vast plan by constant upward striving, so also does it combine easily with political doctrines that emphasize the building of a better world.

The point is that without Lamarckianism, none of the striving and achievement of a parent impacts their progeny’s genetic material. That was a depressing thought for many people (what is the point of striving at all?), and hence there was a clear non-scientific yearning for Lamarckian inheritance to be correct. I use the past tense in referring to these almost 100 year-old arguments, but Koestler’s book and more recent attempts to rehabilitate these ideas tap into these same (misguided) romantic notions. (Odd aside, one of the most positive treatments of this “neo-Lamarckianism” is by Michael Duffy, a frequent climate contrarian Australian journalist). Note that I am distinguishing the classic ‘inheritance of acquired characteristics’ from the much more respectable study of epigenetics.

The scientist-as-hero meme is a very popular narrative device and is widespread in most discussions of progress in science. While it’s clearly true that some breakthroughs have happened through the work of a single person (special relativity is the classic case) and someone has to be the first to make a key observation (e.g. Watson and Crick), the vast majority of scientific progress occurs as the accumulation of small pieces of new information and their synthesis into a whole. While a focus on a single person makes for a good story, it is very rarely the whole or even a big part of the real story. Thus while Koestler can’t be uniquely faulted for thinking that Lamarckianism rose and fell with Kammerer, that perspective leads him to imbue certain events with much more significance than is really warranted.

For instance, one of the more subtle misconceptions in the book though is how Koestler thinks that scientific arguments get settled. He places enormous emphasis on a academic tour that Kammerer made to the UK which included a well-documented talk in Cambridge in which the subsequently-notorious specimen was also in attendance. In fact, Koestler devotes a large number of pages to first-hand recollections of the talk. Koestler also criticises heavily the arch-protagonist in this story (a Dr. Bateson) who did not attend Kammerer’s talk, even though he presumably could have, while continuing to criticise his conclusions. The talk is in fact held up to be the one missed opportunity for some academic mano-a-mano that Koestler presumably thinks would have settled things.

Except that this is not how controversial ideas get either accepted or rejected. Sure, publishing papers, giving talks and attending conferences are all useful in bringing ideas to a wider audience, but they are very rarely the occasion of some dramatic denouement and mass conversion of the skeptical. Instead, ideas get accepted because of the increasing weight of evidence that supports them – and that usually comes in dribs and drabs. A replication here, a theoretical insight there, a validated prediction etc. Only in hindsight does there appear to be a clean sequence of breakthroughs that can be seen to have led inexorably to the new conclusions. At the time, the landscape is far more ambiguous. Thus in focusing on one specific talk, and on its reception by one particularly outspoken opponent, Koestler misses the wider issue – which was that Kammerer’s ideas just didn’t have any independent support. The wider community thus saw his work (as far as I can tell) as a curiosity: possibly his findings were correct, but his interpretation was likely not, and maybe his findings weren’t all that reproducible in any case?

This remains the issue, if Lamarckian evolution were possible, it should have been viewable in hundreds of other systems that were much easier to replicate than Kammerer’s toads (nematodes perhaps?). Absent that replication, no amount of exciting talks will have persuaded scientists. In that, scientists are probably a little different from the public, or at least the public who went to Kammerer’s more public lectures where he was very warmly received.

In these circumstances, it is not surprising that Kammerer’s more vocal opponents would occasionally give vent to their true feelings. Koestler is particular critical of Bateson who, in retrospect, does appear to have gone a little far in his public critiques of Kammerer. However, Koestler perhaps doesn’t realise how common quite scathing criticism is in the halls of academe. This rarely gets written down explicitly, but it is nonetheless there, and forms a big part of how well some people’s ideas are received. If someone is perceived as an exaggerator, or an over-interpreter of their results, even their most careful work will not get a lot of support.

Koestler ends his book with the familiar refrain that since modern science is incomplete, alternative theories must continue to be pursued. He states that since “contemporary genetics has no answers to offer to the problem of the genesis of behaviour”, the replication the key experiments (which he clearly expected to vindicate Kammerer), would very likely make biologists ‘sit up’ and have a long-lasting impact on the field. This notion fails to take into account the vast amount of knowledge that already exists and that makes certain kinds of ‘alternative’ theories very unlikely to be true. The link between this optimistic expectation and discussions of climate change is persuasively demonstrated in this pastiche.

There is one additional characteristic of this story that has some modern resonance, and that’s the idea that once someone starts accepting one class of illogical arguments, that leads them to accept others that aren’t really connected, but share some of the same characteristics. Some people have called this ‘crank magnetism‘. In Kammerer’s case, he was a great believer in the meaningfulness of coincidences and wrote a book trying to elucidate the ‘laws’ that might govern them. Koestler himself became a big proponent of parapsychology. And today there are examples of climate contrarians who are creationists or anti-vaccine campaigners. Though possibly this is just coincidence (or is it….?).

Of course, the true worth of any scientific idea is whether it leads to more successful predictions than other theories. So I’ll finish with a 1923 prediction that Kammerer made while he was on a speaking tour of the US: “Take a very pertinent case. The next generation of Americans will be born without any desire for liquor if the prohibition law is continued and strictly enforced” (NYT, Nov 28).